CL55 Battery flat in 7 days How long should it last?

Cl_a_55y

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I have a 2003 CL55 facelift Kompressor, fully loaded with every extra apart from a wine fridge. It does NOT have a tracker just the stock alarm immobiliser.

If I don't use the car for 7-10 days the battery is always flat. Today after 14 days parked in fine weather it was flat. There was enough to turn the alarm off and open the central locking but the dash display just flashed a few times when the ignition key was turned, so I didn't bother trying to start it. (I find Keyless Go triggers more items to power on than ignition key starting.)

Locking, alarm and mirror fold still worked afterwards but the powered boot lid failed to open. So there was a little charge in it but not much. If I charge the battery it is ok again unless I don't use the car for a week or so.

Last November the alternator was checked ok, so too was the battery but it was nearly 6 years old so I replaced it and had no problems until March when it started going flat again. I had the battery tested again in July. They said it was ok but replaced it anyway under warranty with another Exide unit.

I have looked at all the posts on here and have been looking at a CTEK XS300 charger and conditioner which I feel will solve the problem.

I am by the way disabled so cannot do as much DIY stuff as I once did. I do have a Fluke meter though so can check volts and amps if someone can give advice on what readings I should get and when. Also any known problems with items that stay live drawing power when they shouldn't?

The local Merc dealer told me it takes 30 mins for all systems to shut down once you park the car and that it takes 8 miles to recharge the amount taken out to start the car. Oh and it could be very expensive to diagnose! No surprise there then!! :lol:

Oh I did find a problem a while ago by sitting in the car in the dark one night and that was that the glovebox light stayed on when closed (saw a sliver of light) even though the lights, ignition and ALL other ancillaries were turned off and alarm and locking turned on. I fixed the faulty switch and hoped for the best. It was a Eureka moment but a week later it was flat again!! :mad:

So...

How long you should be able to leave a CL55 parked unused and still be able to start it?
How can I check the battery and alternator myself?
Is the CTEK charger / conditioner the way to go?

All advice gratefully received.
 

teddycatkin

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Sounds like the glove box light again --or another undiscovered drain on the system ?
It should stand 6-8 weeks and still be ok with a new battery.(make sure you have the biggest and best battery you can get ? not sure on exide we use bosch silver).
We have similar problems with keeping classic cars and not running them from one week to the next and rather than use a trickle charger just disconnect one battery terminal if its going to be left longer .
You can buy batt terminal that is a push on and fasten without using spanners--but I guess on yours the battery may not be as easilly accessable.
Best plan is to try and run it at least once a week and also find out if something is using the power when its left standing ?
 

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To check the battery drain the ammeter has to be in series with one of the main battery leads, it does require an ammeter that can handle at least 10 amps to allow for the shutting down of the wake up system.

When you first turn off the drain will be at around 8 amp, this will fall away in steps next dropping to 2 and then settling down the the normal drain of around 45-50ma. This is the figure that one would hope to achieve or less. This all takes about 20mins.

On cars with short or leaks, there can be problems in that if you break the continuity, then the path of the short can go away, but it would seem that you short circuit is permanent. I use a clamp meter as this does not require the meter to be put in series so that the circuit does not get broken.

So the best that you can do is to have the battery fully charged and then put your ammeter in series with either of the battery leads, and see what the readings are.

Please report back with what you find.

A little about circuits.

When the voltage on the battery gets to a certain low point, say around 10 something volts, circuits cannot re set and the current may go very high when this happens, discharging the battery rapidly from this point on, so it is important that the test are done with a fully charged battery to avoid false readings
 
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Cl_a_55y

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it does require an ammeter that can handle at least 10 amps

My Fluke meter has a max range of 10Amps so I presume this is not high enough?

I found this Automotive Current Tester in Maplins http://www.maplin.co.uk/Module.aspx?ModuleNo=217879 would this be any good for my needs? Is there a suitable blade fuse on the main supply for this? I can see this might help to narrow down the search for a short circuit though? If I can get to all the fuses?

I also found this http://www.digital-meters.com/products/AC%7B47%7DDC-Voltage-&-Current-Clamp-Meter-%252d-Tecpel-DCM%252d033.html Now if I get this right the clamp goes around the cable insulation? If so with a meter like this since my battery is in the boot I would need to be shut inside the boot for 20 mins for the test you recommend? :eek: :lol: EDIT I just noticed the DC scale on this is from 40A - 400A so I guess this wouldn't be any good either?

Is it possible to find a suitable clamp ammeter for less than £45? Still I guess that's less than 30mins of a main dealer labour rate?
 
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mikestrivens

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I was looking at getting one for myself and found the Sealey MM405 on Amazon to be about the only one reasonably priced (£66) that handles small automotive current - with a DC amps range from 0 - 200. I would also be interested if there any others.
 

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I think that your fluke will do fine to start with to know if you have got a leak somewhere, once it has been established that you have then the ammeter with the spade fuse connector is good for plugging into the individual fuse holders, in the known circuits that can give leaks. Sure you could start off there if you wish in the first place checking things like seat controllers and the OVP.

I used all kinds of meters some 12 in all. the clamp meter that I bought has a resolution of 1ma on the 4 amp range, and has a max range of 80 amp, and this is what is needed, it only cost under £35 and the only one that I know of at that price (CPC)

Second thoughts, buy the plug in meter and you can work your way through the fuse boxes.
 

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Cl_a_55y

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I was looking at getting one for myself and found the Sealey MM405 on Amazon to be about the only one reasonably priced (£66) that handles small automotive current - with a DC amps range from 0 - 200. I would also be interested if there any others.

I found a few DC clamps... This is a simple Sealey 75A clip on analog meter http://www.tooled-up.com/Product.asp?PID=26759&Referrer=shopzilla&referrer=shopzilla I guess it might do the job but less accurate being a small analog scale.

These are clamp meters I found but I'm still working out what is the best one to go for...

http://cpc.farnell.com/jsp/search/productdetail.jsp?sku=IN05240 This goes up to 1000A DC and AC. £55.91 shipped

http://cpc.farnell.com/jsp/search/productdetail.jsp?sku=IN05110 This is cheaper and goes up to 400A DC and AC which I presume should be enough for most non industrial purposes? £37.84 shipped

http://cpc.farnell.com/jsp/search/productdetail.jsp?sku=IN05111 This one is a little more expensive and has TrueRMS AC measurement which I presume is more accurate? £50.83 shipped

I also found some Clamp accessories for my Fluke meter but the cheapest (Pico) was around £80 and the genuine Fluke ones are over £200!

I am still looking and trying to understand what I need and how to use it!! :confused:

update... CPC have 42 clamp meters but many don't measure DC current... still working through them!

Malcolm I think this is the one in your photo? http://cpc.farnell.com/_/in05268/clamp-meter-1ma-res/dp/IN05268 It is now £53.51. I noticed it only has a 12.5mm jaw opening... I think I have cables fatter than that? There are cheaper ones (see above links) but I'm not sure how low their resolution is few state it in the specs.
 
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Cl_a_55y

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I think that your fluke will do fine to start with

Malcolm thanks for your help...

How much current is drawn from the battery when shutting down? What if the radiator fans were running? I have a few 60A fuses. I guess the highest draw is the starter motor? What is that for instance? I'm just thinking if I am going to buy a clamp meter I might as well get one that goes to at least 60A or 75A? Also though one which goes down to a low resolution.

I have found out that the Tenma 72-7224 & 7226 Clamps have a 400A max but a 10mA resolution. Maybe this is too high?

The ST-3343 (no brand name) IN05240 on CPC (linked to in a previous post) has a 1KA max but with a 1mA resolution it also has a wider range of functions so I think it may be the best option for me for an all round meter at £55.91

However surely a few mA is so small it would take months to flatten a big 100ish Amp/hr battery? If I have a short capable of flattening the battery in a week or so how big a current draw would I expect to see?

Lastly I have also had an SRS error on the car but that has been appearing ever since I bought the car in 2006. I think it is caused by the passenger seat sensor pad? Could this be causing the drain when the car is parked?

Thanks again for your help

Steve
 
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muller1

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Battery Drain

Roughly if you have a 100ah battery 1 amp over 100 hours will flatten it totally.
That assumes that the battery reads almost 0 volts at the end of 100 hours.
1 week is 168 hours and in theory you would need a drain of just over 1/2 amp to drain the battery.
I could be a bit out and I am sure someone will have a better handle on this but I do not think I am 100% wrong.

Regards.

Mike
 
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Cl_a_55y

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That assumes that the battery reads almost 0 volts at the end of 100 hours.

Thanks Mike, I did a similar calculation myself however I read today on CTEK battery conditioner site that usually a battery will only go down to about 6-7 volts before everything ceases to function so on that basis it would go flatter even sooner! Mine usually has a small amount of power left but not enough to start the car however an attempt at starting it usually finishes it off and then I lose all my settings too.

I wonder what the normal expected current drain on a parked locked and alarmed CL55 in full working order is? I guess the information must be in a workshop manual somewhere?
 

Rappey69

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Another thing about lead acid batterys is that you should not discharge them more than 25% from full. They are designed to have a large load put on them (starting) then a high power recharge (when engine running).
They do not like being slowly discharged.
Flatten one 12 times and it is damaged to the point that it is ready for the bin.
Deep cycle batterys are also available, these can have 75% of their charge removed and have no problem with slow discharge but most are not happy with a heavy demand when starting.
 

amwebby

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The normal expected drain is 30-35ma. I had the same problem which was traced to a faulty seat controller, a common problem apparently.
 

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Thanks Mike, I did a similar calculation myself however I read today on CTEK battery conditioner site that usually a battery will only go down to about 6-7 volts before everything ceases to function so on that basis it would go flatter even sooner! Mine usually has a small amount of power left but not enough to start the car however an attempt at starting it usually finishes it off and then I lose all my settings too.

I wonder what the normal expected current drain on a parked locked and alarmed CL55 in full working order is? I guess the information must be in a workshop manual somewhere?

The acceptable figure is under 50ma,,40 is better and normal
 

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I have already spelled out the dangers of trying to test when the battery is not charged up,,once the voltage is down the current will soar as the ECU cannot re set. Forget the clamp meter (they need skill in using)get the plug in to the fuse one.

I have written out all that you need to do, more than once
 
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Cl_a_55y

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The normal expected drain is 30-35ma. I had the same problem which was traced to a faulty seat controller, a common problem apparently.

Where is the seat controller? In the seat or elsewhere? Is this a controller for all electric seat adjustment functions? What about the massage and cooling / heating? Same thing or are they different?

I guess I can pull the fuses for various functions and see what effect it has when I'm metering the ampage.

Thanks for your input.
 
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Cl_a_55y

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I have already spelled out the dangers of trying to test when the battery is not charged up,,once the voltage is down the current will soar as the ECU cannot re set. Forget the clamp meter (they need skill in using)get the plug in to the fuse one.

I have written out all that you need to do, more than once

I seem to have upset you Malcolm?

If so I apologise. I am just trying to get to grips with this and keep the costs down as much as possible. I'm sorry I missed some of the detail like normal current draw when I initially read your first post. Maybe it just went over my head at that point in time? I have learned a lot more since! Sorry again :Oops:

Regarding testing when battery wasn't fully charged, I understood that and didn't question it, so I'm puzzled why you spelled that out again? The battery is fully charged now and will remain so for a while as I will be driving it daily this week.

Re the clamp meter I'm sure I have the necessary skill since I was a telecoms and mainframe computer engineer for 35 years before I became disabled!! However, my knowledge of modern complex car electronics is limited but I am learning fast. Also I never had the need to use a clamp meter before but providing you get the cable straight and square in the jaws it should be accurate enough and saves disconnecting power, which should avoid the problem you mentioned that disconnecting could temporarily clear the fault.

What concerned me earlier were your comments about connecting my 10Amp max rated Fluke in series and having to disconnect the leads on the battery and thus losing all my settings etc. Also the fact I didn't want to blow the Fluke up! So I figured the clamp meter would be a better option.

My son will be back from holiday soon and I will get him to help me to test the drain with my Fluke meter asap and report back.

Thanks again and I do appreciate you sharing your knowledge Malcolm.

Regards

Steve
 

amwebby

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Where is the seat controller? In the seat or elsewhere? Is this a controller for all electric seat adjustment functions? What about the massage and cooling / heating? Same thing or are they different?

I guess I can pull the fuses for various functions and see what effect it has when I'm metering the ampage.

Thanks for your input.

The seat controller is under the seat and controls all seat functions on that side (there are two) and a few other functions. In my case it was the drivers side, which is the side that most commonly causes problems as you might expect. The only indication I had that something was awry was that the easy exit had ceased to work, which is controlled from the unit on this side.
 
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Cl_a_55y

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The only indication I had that something was awry was that the easy exit had ceased to work, which is controlled from the unit on this side.

Thanks for that. My seat control has played up a few times in the last 3 years but usually it sorts itself out again after I use the door controls to move the seat up and down or forward and back. I presumed there is a reset function for the seats like there is for the roof and windows?

My passenger seat has a dodgy SRS detection pad too so if it is the seat controller it sounds like I might be in for an expensive time with seats!
 

amwebby

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Thanks for that. My seat control has played up a few times in the last 3 years but usually it sorts itself out again after I use the door controls to move the seat up and down or forward and back. I presumed there is a reset function for the seats like there is for the roof and windows?

My passenger seat has a dodgy SRS detection pad too so if it is the seat controller it sounds like I might be in for an expensive time with seats!

The seat controller is some £200. If yours is playing up it may well be the culprit, it usually is. Fitting was an hours labour, £45 at my local dealer as I get a discount on parts and labour by virtue of my car being over six years old. I wasn't unhappy. :cool:
 


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